<?php
if(isset($_POST['md5']))
{
	echo '<h3>Uw MD5 hash: <span style="font-weight: normal">' . hash('md5', $_POST['md5']). '</span></h3>';
}
?>
<p>
<form method="post">
	md5 hash: <input name="md5" /><br /><Br />
	<input type="submit" value="Maak hash" />
</form></p>